81280995 has 16 divisors (see below), whose sum is σ = 137700000. Its totient is φ = 40799744.

The previous prime is 81280981. The next prime is 81281017. The reversal of 81280995 is 59908218.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 81280995 - 2⁹ = 81280483 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 159120 + ... + 159629.

It is an arithmetic number, because the mean of its divisors is an integer number (8606250).

Almost surely, 2^81280995 is an apocalyptic number.

81280995 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

81280995 is a deficient number, since it is larger than the sum of its proper divisors (56419005).

81280995 is a wasteful number, since it uses less digits than its factorization.

81280995 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 318774.

The product of its (nonzero) digits is 51840, while the sum is 42.

The square root of 81280995 is about 9015.5973179818. The cubic root of 81280995 is about 433.1746207067.

The spelling of 81280995 in words is "eighty-one million, two hundred eighty thousand, nine hundred ninety-five".